Subsidiary triple valve for air-brake apparatus



Patented` Aug. 18, 1925.

CHARLES W. CROMETON, Oli' GGDEN, UTAH.

SUBSIDIARY TRIPLE VALVE FO'R AIR-BRAKE APPARATUS.

Application filed May 15,

T0 all whom t may concern.'

Be it known that I, Cr-IAnLns W. @noirs TON, a citizen of the United States, and resident of Ogden, in thecounty of `Weber and State of Utah, have invented certain new and useful Improvements in Subsidiary Triple Valves for Air-Brake Apparatus, of which the following is a specification.

The existing air brake systems (notably the l/iestinghouse and New York air brake) are admirably adapted for train control within the limits of their capacity. For passenger service they are ideal. The freight equipment of these systems are likewise highly efficient on trains of moderate length. l/Vhere an engine Vis hauling a train of over forty or fifty cars, the existing air brake systems are defective dueto the inability'of the mechanism to function fully in releasing the air brakes at the rear portion of the train. The present equipment is unable to supplysufiicient volumeof air to release the brakes of the rearcars, and also recharge the auxiliary reservoirs at the proper time when using the air brake system on grades.

The provisions at present made to overcome this recharge of auxiliary reservoir defect is the employment of a pressure reu taining valve on each car. This valve is not automatic but is hand operated. Tt is used only when the recharge of auxiliary reservoirs exist, which follows after each application of the air brake system. l

It is a very dangerous condition for the `trainmen and its use requires them to operate the retaining valves on grade by hand.

Many lives have been lost in the actuation of these valves.

My invention does away under actual braking conditions with the use of the air der pressure is lost through leakage in the retaining pipes and its connections.

The cause of the defects above noted is systems. retaining valve, although its retention is.` permissible. A. great deal of brake cylin-` The charging action at 1924. Serial No. 713,580.

action in recharging the auxiliary reservoirs for the rear cars of a long train.

The triple valve has several important functions to perform. It complies satisfactorily with `all the conditions required of it on trains of moderate length. The triple valve is an ingenious device, of marvellous adaptability for the purpose of control of trains cf moderate lengt But the limitations imposed upon its design render it unsuitable for the rear cars of long trains.

lThis is due to the small feed `groove in thev triple valve, through which the auxiliary reservoir is charged, and which delays its action. This groove can not be enlarged, because of the number of important functions which the triple valve must perform and their conjoint operation.

llt therefore becomesnecessary at present to provide a pressure retaining valve for each car. The hand operation of this valve retains the brake cylinder pressure and prevents the release of the brakes .on down grades while the auxiliary reservoirs at the rear are being slowly recharged.

I do away with the necessity for such a condition with attendant saving `of life through the personal handling of these retaining valves.

The inability to release the brakes on the rear of long trains at the proper time and under proper conditions increases very highly the percentage of flat treads and cracked wheels. Y

Existing air brake apparatus is unable to supply air at the rear of long trains in suficient volume to the system to release the br kes after service.

My device is used with existing air brake By its use an additional volume of stored air is automatically supplied espe cially on long trains where it is essential that the air brake system be entirely automatic if life is to be conserved. My invention decreases the number of flat, cracked and burnt wheels, due to sliding, and obviates other expensive and dangerous defects dueto the inadequate operation of the triple valve for long trains, and the sticking, leaks, friction, and the like attendant upon its use under such conditions.

The provisions at present made toV overcome this release defect are very inefficient, having to be supplied directly from the locomotive.

The use of my device upon the locomotive or upon any one or more, or upon all of the cars does not reduce the effectiveness .et the cars not equipped with my device which may be coupled up in the train. My device also prevents an overcharge of the auxiliary reservoirs on the liront end ot long trains.

The accompanying drawing shows a vertical sectional view ot the apparatus oi my invention.

Like the triple valve my automatic device has three main valves which function separately and primarily as a volume, an overcharge and a quick charge device.l lt might properly be called a subsidiary triple valve. Indeed it should be located in the branch train pipe as close tothe triplo valve as possible. ln the description tor purposes of clearness, it Will be called the subsidiar as a short title vlier identifying it.

T he subsidiary is a unit in the branch pipe close to the triple valve. r'he branch pipe enters at ifi and leaves at B Where it the triple valve. 'lhe volume valve device C connected With the branch passage at D is also inconnnunicationYivith a storage reservoir E by pipes F and G. rl`he branch pipe also connects ivith the valved overch arge device H at l.

The quick charge valve device J and the overcharge 'H are connected by the passage K and a passage L leads from quick charge valve J to the usual auxiliary reservoir.

Then the brake pipe pressure is on the r system it enters volume device C passing through a feed groove in the piston valve to the pressure limiting chamber and is charged to the pressure in the brake pipe. rl`his pressure increases or diminishes with that in the 'brake pipe system Which is kept Within predetermined limit-s.

Then brake pipe pressure increases beyond a given point the piston valve in the volume device C 'rises against spring pressure be'lore the pressure in the limiting chamber has time 'to equalize itseliC with the brake pipe pressure. ln thisrisingl it opens a feed groove in the piston and admits brake pipe pressure to the volume reservoir E through the connecting passage F and charges the same until pressure limiting` chamber has equalized ivith brake pipe pressure.

Another passage G connects the subsidiary triple valve and the reservo-ir E to assist in charging the latter. lt has a check valve closing against discharge to brake pipe.

lWhen the pressure limiting chamber of the 'volume device has equalized 1with the brake pipe pressure the spring seatsthe pis- 'ton valve and cuts out the volun'iereservoir,

Which has been charged to brake pipe pressure, and :holds it in reserve for releasing purposes Whenever a reduction of pressure causes a differential or reduction, say of not less than sin pounds lor the equalizing pressure in the limiting chamber oiu the volume device C.

W hen the valve oi the air brake system is moved to ull release position the brake pipe pressure increases very rapidly. lt forces volume piston valve upwardly compressing its spring and also the second pressure adjusting` spring set at about two pounds.)

rlhe increased. pressure upon the volume piston just described opens the volume reservoir pipe l? to supply a supplementary pressure ot air to the brake pipe for releasing the triple valves on long trains.

rlhe louer volume piston rod is a cut out valve for the leed groove in the piston bushing. rllhe upper piston rod is a guide for the lower one. The upper pressure adjusting spring is regulated by a nut. ln practice it should not esceed tivo pounds pressure independent o't the brake pipe pressure. rl`he extension nut locks the adjusting nut. The sal-'ety cap excludes extraneous matter, and makes the device air tight.

Having described the volume section of the subsidiary triple valve, the overcharge section will noiv be taken up.

Passages A. B D and l are all in communication with the branch pipe at A. lt is this over-charge action Which cuts brake pipe pressure from entering the auxiliary reservoir through the subsidif` valve. Ats check valve l closes when pressure'in the auxiliary reservoir7 plus the pressure oic the spring.;` on the check valve exceeds the standar( brake pipe pressure. This pressure is greater on the front end oi trains and causes an overcharge in the auxiliary reservoir.

Then over-charge check valve rises the brake pipe air enters through quick charge section o'f my subsidiary triple valve. resulting in an action to be described further on a'tter the details of overcliarge section are indicated.

Valve P has brass lnishing and valve seat and a valve steil; guided by an adjusting n it screu'cd into the oif'erehargo valve chamil spring surrounds the valve stem and is adjusted by the mit say twenty pounds pressure. il safety cap covers the overcharge valve section.

rlie q ck charge section oimy subsidiary triple v 7e ope ates when overcharge valve l) opens. Brake pipe pressure enters passage li. to the ck charge piston Q and rpasses ,cro-ove in the piston -Wall say or si teen to twenty live seconds,

inber above the piston. Thence it eh the pipe L to tne auxiliary say at seventy pounds brake pipe pressure.

lt will be noted that thisquick charge section of my suosidiary assists very materially in charging the auxiliary reservoirs.

lce

"In the present equipment this action is very slow owing to the necessarily limited size of the feed groove in the triple valve-a feed groove Which is likelyto become corroded with extraneous matter and thus further decrease its efficiency. Such defective apparatus also requires the use of hand operated pressure retaining valves on each car as described elsewhere and not necessary With my invention.

It should also be noted that there is a retarding effect on this quick charge section of my subsidiary triple valve functioning on the front end of long trains and giving a uniform and very quick charge of the auxiliary reservoirs after every application of the train brakes.

The pressure in branch passage K upon opening valve l?, also admits air by a by-pass lt, to the chamber S above the piston Q, acting to retard its upward motion. This tends to retard the charging of the auxiliary reservoirs on the front end of long trains lt gives a uniform pressure to the auxiliary reservoir by supplying more air to the rear of trains and less to the front.

The retarding device has a brass bushing M seating air tight on a retarding valve having a seat thereon. rThe bushing M has a feed groove in its side connecting with the luy-pass lt and forms the retarding air port. It charges the auxiliary reservoir say at the rate of forty te fifty pounds plus triple valve feed groove charge.

The restriction in the port of the bushing varies in areas due to differentials in pressure of the quick charge and retarding valves.

The device operates When retarding valve spring in chamber S is compressed and is regulated to act automatically when the car is located in the train say forty or more cars from the front. Retardation occurs vvhen quick charge piston Q rises and cuts out the full charge port in the piston Wall and opens the retarding valve, allowing air in chamber S to feed through groove in the bushing connecting with by-pass R at brake pipe pressure to the auxiliary reservoir through the pipe L.

To the rear of said forty cars the pressure is not sufficient to raise the reta-rding spring. Thereafter air is fed at full feed pressure to charge the auxiliary reservoirs.

`While charging long trains, the adjustment of the quick charge top cap of the quick charge section serves to regulate the retarding valve.

rlhe application of the brakes by reducing the pressure during service or emergency has no effect on the subsidiary triple valve. lThere is at such times no communication between the brake pipe and the volume or auxiliary reservoirs. The triple valves function independently of the subsidiary triple valve.

rlhe volume reservoir E maintains a large volume of air which is automatically fed to the brake pipe When the engineer releases the brakes through the cab valve on the locomotive. The pressure is therefore rapidly increased and it forces the triple valve piston to release position. The volume reservoir and its quick release valve C act to assist the engineer after a brake application to release the brakes and restore the brake pipe volume of air.

When the proper brake pipe pressure is reached valve P opens and the auxiliary reservoir is charged as elsewhere described` lf the subsidiary triple valve is located on a car at the front of a long train Where the volume of air is greater the auxiliary-reser-A voir valve device J is actuated and said reservoir is charged as set forth elsewhere. This action permits the brake pipe volume of air a. chance to flovv more rapidly toward the rear of the train and causes a very quick and uniform charge of all the auxiliaries on a long train. Say thirty cars to the rear the quick charge device J does not come into action because of the better equalization of the air flow through the brake pipe. It Will thus be perceived that this device is auto matic regardless of the point Where a particular subsidiary triple valve is located in the train.

My subsidiary triple valve functions auto matically With all the standard brake systems Without any alteration or modification thereof.

Claims:

1. Automatic air brake apparatus having` means accessory of its triple valve consisting of a subsidiary triple valve provided With means independent of the auxiliary reservoir for storing air at air brake pres sure, means for automatically charging the auxiliary reservoir from such s-tored air upon excessive brake pipe pressure, and means for regulating the charging means operative to equalize the pressure in the auxiliary reservoir.

2. Automatic air brake apparat-us having means accessory to its triple valve consisting of a subsidiary triple valve provided With means for maintaining an increased volume of stored air in a container separate from the auxiliary reservoir, means for increasing the brake pipe volume pressure and for recharging the auxiliary reservoir from the container after application of the brakes.

CHARLES W. GRGMPTON, 

